Ionization Energies

Ionization Energies Navigation

By Name

By Symbol

By Number

Actinium to Cadmium

Calcium to Copper

Curium to Iron

Krypton to Molybdenum

Neodymium to Roentgenium

Rubidium to Technetium

Tellurium to Uranium

Vanadium to Zirconium

Element

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Neodymium

I (1)

5.5250 eV

II (2)

10.72 eV

III (3)

22.1 ± 0.3 eV

IV (4)

40.4 ± 0.4 eV

Neon

I (1)

21.56454 eV

II (2)

40.96296 eV

III (3)

63.45 eV

IV (4)

97.12 eV

V (5)

126.21 eV

VI (6)

157.93 eV

VII (7)

207.2759 eV

VIII (8)

239.0989 eV

IX (9)

1195.8286 eV

X (10)

1362.1995 eV

Neptunium

I (1)

6.2657 eV

Nickel

I (1)

7.6398 eV

II (2)

18.16884 eV

III (3)

35.19 ± 0.02 eV

IV (4)

54.9 ± 0.2 eV

V (5)

76.06 ± 0.06 eV

VI (6)

108 ± 2 eV

VII (7)

133 ± 2 eV

VIII (8)

162 ± 2 eV

IX (9)

193 ± 2 eV

X (10)

224.6 eV

XI (11)

321.0 eV

XII (12)

352 ± 2 eV

XIII (13)

384 ± 2 eV

XIV (14)

430 ± 2 eV

XV (15)

464 ± 2 eV

XVI (16)

499 ± 2 eV

XVII (17)

571.08 ± 0.12 eV

XVIII (18)

607.06 ± 0.06 eV

XIX (19)

1541 ± 1 eV

XX (20)

1648 ± 3 eV

XXI (21)

1756 ± 4 eV

XXII (22)

1894 ± 4 eV

XXIII (23)

2011 ± 4 eV

XXIV (24)

2131 ± 4 eV

XXV (25)

2295 ± 5 eV

XXVI (26)

2399.2 ± 0.6 eV

XXVII (27)

10288.8 ± 2.0 eV

XXVIII (28)

10775.48 ± 0.06 eV

Niobium

I (1)

6.75885 eV

II (2)

14.0 eV

III (3)

25.04 eV

IV (4)

38.3 eV

V (5)

50.55 eV

VI (6)

102.057 eV

VII (7)

125 eV

Nitrogen

I (1)

14.5341 eV

II (2)

29.6013 eV

III (3)

47.44924 eV

IV (4)

77.4735 eV

V (5)

97.8902 eV

VI (6)

552.0718 eV

VII (7)

667.046 eV

Nobelium

I (1)

6.65 eV

Osmium

I (1)

8.43823 eV

Oxygen

I (1)

13.61805 eV

II (2)

35.1211 eV

III (3)

54.9355 eV

IV (4)

77.41353 eV

V (5)

113.8990 eV

VI (6)

138.1197 eV

VII (7)

739.29 eV

VIII (8)

871.4101 eV

Palladium

I (1)

8.3369 eV

II (2)

19.43 eV

III (3)

32.93 eV

Phosphorus

I (1)

10.48669 eV

II (2)

19.7695 eV

III (3)

30.20288 ± 0.00012 eV

IV (4)

51.4443 ± 0.0002 eV

V (5)

65.02564 ± 0.00021 eV

VI (6)

220.423 ± 0.012 eV

VII (7)

263.57 ± 0.06 eV

VIII (8)

309.60 ± 0.10 eV

IX (9)

372.13 ± 0.19 eV

X (10)

424.43 ± 0.25 eV

XI (11)

479.46 ± 0.12 eV

XII (12)

560.8 eV

XIII (13)

611.74 ± 0.07 eV

XIV (14)

2816.93 ± 0.04 eV

XV (15)

3069.866 ± 0.008 eV

Platinum

I (1)

8.9588 eV

II (2)

18.563 eV

Plutonium

I (1)

6.0260 eV

II (2)

11.2 eV

Polonium

I (1)

8.414 eV

Potassium

I (1)

4.3406633 eV

II (2)

31.63 eV

III (3)

45.806 ± 0.010 eV

IV (4)

60.91 ± 0.05 eV

V (5)

82.66 ± 0.16 eV

VI (6)

99.4 ± 0.2 eV

VII (7)

117.56 ± 0.10 eV

VIII (8)

154.88 ± 0.05 eV

IX (9)

175.8188 ± 0.0030 eV

X (10)

503.8 ± 0.6 eV

XI (11)

564.7 ± 1.0 eV

XII (12)

629.4 ± 1.2 eV

XIII (13)

714.6 ± 1.4 eV

XIV (14)

786.6 ± 1.6 eV

XV (15)

861.1 ± 1.7 eV

XVI (16)

968 ± 2 eV

XVII (17)

1033.4 ± 0.1 eV

XVIII (18)

4610.8 ± 0.9 eV

XIX (19)

4934.084 ± 0.013 eV

Praseodymium

I (1)

5.473 eV

II (2)

10.55 eV

III (3)

21.624 ± 0.003 eV

IV (4)

38.98 ± 0.02 eV

V (5)

57.53 ± 0.05 eV

Promethium

I (1)

5.582 eV

II (2)

10.90 eV

III (3)

22.3 ± 0.4 eV

IV (4)

41.1 ± 0.6 eV

Protactinium

I (1)

5.89 eV

Radium

I (1)

5.278423 eV

II (2)

10.14715 eV

Radon

I (1)

10.7485 eV

Rhenium

I (1)

7.83352 eV

Rhodium

I (1)

7.45890 eV

II (2)

18.08 eV

III (3)

31.06 eV

Roentgenium

I (1)

10.5 eV

References (Click the next to a value above to see complete citation information for that entry)

Lide, David R., editor. CRC Handbook of Chemistry and Physics, 88th edition. Boca Raton, Florida: Taylor & Francis Group, 2008.

Martin, W. C., Romuald Zalubas, and Arlene Musgrove. "Energy Levels of Phosphorus, P I through P XV." Journal of Physical and Chemical Reference Data, volume 14, number 3, 1985, pp. 751–802.

Martin, W. C., Romuald Zalubas, and Lucy Hagan. Atomic Energy Levels—The Rare-Earth Elements. Washington, D.C.: National Bureau of Standards, 1978.

Moore, Charlotte E. Ionization Potentials and Ionization Limits Derived from the Analyses of Optical Spectra. Washington, D.C.: National Bureau of Standards, 1970.

Sansonetti, J. E., and W. C. Martin. "Handbook of Basic Atomic Spectroscopic Data." Journal Of Physical And Chemical Reference Data, volume 34, number 4, 2005, pp. 1559–2259. doi:10.1063/1.1800011

Seaborg, Glenn T., and Walter D. Loveland. The Elements Beyond Uranium. New York: John Wiley & Sons, Inc., 1990.

Sugar, Jack, and Charles Corliss. "Atomic Energy Levels of the Iron-Period Elements: Potassium through Nickel." Journal of Physical and Chemical Reference Data, volume 14, number 2, 1985, pp. 1–664.